1. Field of the Invention
The invention relates to a vehicle headlamp control device.
2. Description of Related Art
A headlamp control device is known, which controls an upper limit irradiation position of a headlamp when a front pedestrian in front of a vehicle is detected, so that the upper limit irradiation position becomes lower than the face of the front pedestrian (for example, Japanese Patent Application Publication No. 2000-225888 (JP 2000-225888 A)). By controlling the upper limit irradiation position of the headlamp so as to be lower than the face of a pedestrian, glare protection for the pedestrian becomes possible.
There is also known a lighting system that irradiates an area in front of a vehicle with near infrared and images the area in front of the vehicle by receiving reflected light of the near infrared, or carries out pulse irradiation of visual light for a period of time that is short enough to prevent a pedestrian from being dazzled, and images an area in front of the vehicle when the pulse irradiation is carried out (for example, Japanese Patent Application Publication No. 2009-90844 (JP 2009-90844 A)). Thus, it is possible to detect a pedestrian in front of a vehicle at night without making the pedestrian dazzled.
However, in the case where a pedestrian in front of a vehicle is detected based on an image captured by a camera, the pedestrian is detected by pattern recognition including image information of a face. Therefore, like JP 2000-225888 A, there are cases where a pedestrian cannot be detected without light irradiation from a headlamp on the face. As a result, when a pedestrian is not detected as stated above, the face of the pedestrian is irradiated by the headlamp, and, once the face of the pedestrian is irradiated, the pedestrian is detected, and the face of the pedestrian is no longer irradiated. This situation is repeated, which can make it impossible to appropriately carry out glare protection for the pedestrian. In short, it may be impossible to achieve both detection of a pedestrian based on an image captured by a camera, and glare protection for the detected pedestrian.
Meanwhile, as stated in JP 2009-90844 A, it is possible to detect a pedestrian in front of a vehicle at night by carrying out near infrared irradiation or pulse irradiation of visual light without making the pedestrian dazzled. However, it is necessary to use a camera that is able to capture an image by receiving near infrared or pulsed light for a very short period of time. In short, it is not possible to achieve both detection of a pedestrian based on an image captured by the camera, and glare protection for the detected pedestrian without changing a basic performance of the camera.